This artist's rendering shows Sima de los Huesos hominins who are estimated to have lived approximately 400,000 years ago during the Middle Pleistocene period.

Written by

Traci Watson
| Special for USA Today

In a scientific tour de force, researchers analyzing a scrap of bone from an ancient human have extracted DNA at least 300,000 years old, more than double the age of the next-oldest genetic material found.

The achievement could set off a rush to find more human DNA of a similar age, which some experts had once regarded as a nearly impossible goal.

The DNA itself suggests an unexpected link between the Spanish human it came from and ancient humans in Siberia, creating further confusion about a period in human evolution known as "the muddle in the middle." ...